1. Field of the Invention
The invention generally relates to a device that simulates the appearance of and vascular function within a torso for medical training purposes. Specifically, the invention is a torso simulant with blast and/or penetration injuries suitable for use as a training device for stemming blood loss. The training simulant includes compressible areas that permit a tourniquet to collapse a compressible tube simulating vascular elements.
2. Background
Advancements in personal-protection technologies, examples including but not limited to helmets and body armor, have greatly reduced the frequency and severity of blast-induced and impact-related injuries. However, current technologies significantly compromise mobility when adapted to protection of the lower torso and legs. This means that soldiers are equipped with protective elements to prevent and to minimize injuries to both head and upper torso while leaving both lower torso and legs unprotected.
Enemy combatants are well aware of the technical limitations of and the tradeoffs imposed by personal-protection technologies. It is now common for improvised explosive devices (IEDs) to target the lower torso and/or the legs in pursuit of exploiting the absence of protective elements along these regions. Consequently, wounds to the lower trunk and legs are more frequent. While the damage cause by IEDs is often not immediately fatal, the resultant blood lose could be significant and may cause death.
An abdominal tourniquet is one tool used by soldiers to stem blood loss caused by penetrating wounds and severed legs. One exemplary tourniquet is the Abdominal Aortic and Junctional Tourniquet (AAJT) sold by Compression Works, LLC located in Hoover, Ala. The AAJT and other similar tourniquets are placed about the lower torso and properly positioned to apply a compressive force onto vascular elements within the torso in order to stem blood flow to and from injuries along the lower trunk and legs.
Successful use of an abdominal tourniquet is wound specific and therefore inherently difficult to properly implement. For example, a user must properly identify the compromised vascular element(s), properly identify the area(s) onto which pressure is applied to stem blood loss, and properly apply the appropriate pressure without causing additional injury to and/or death of the injured person.
Mannequins replicating the torso and other body parts are available for training soldiers as to the treatment techniques required to stabilize a wounded soldier. Mannequins replicate the appearance and properties of flesh, tissues, and organs, as well as injuries thereto. Mannequins may include tubes which allow a liquid simulating blood to flow to and out of an injury representative of an impact wound or a blast-induced wound. Presently know training devices are problematic for at least the following reasons.
The torso region of mannequins fails to realistically simulate the mechanical response of skeletal elements, flesh, tissues, and vascular elements to the compression applied by a tourniquet. For example, it is common for the compressible materials surrounding a vascular simulant to locally move in the direction of the applied force thus compressing the materials surrounding the vascular simulant without closing the vascular simulant and without choking blood flow. The result is functionality that does not accurately correspond to the mechanical response of a torso after application of pressure by a tourniquet, thus negating the training value of mannequins.
In U.S. patent application Ser. No. 13/925,949 entitled Simulant with Vascular Structure Mechanically Responsive to a Tourniquet, a simulant is described including a compressible body, a structure, a compressible tube, and a pair of plates. The compressible body simulates the appearance and properties of a body part. The structure simulates an injury disposed along the compressible body. The compressible tube simulates a vascular element, examples including but not limited to an artery or a vein. The plates are disposed within the compressible body and separately disposed about the compressible tube. The plates are rigid and configured to deform the compressible tube when a compressive force is applied onto the compressible body by a tourniquet or the like. The compressible body and plates are cast separately and the plates are inserted into a preformed cavity within the compressible body.
Unlike the simulant in the aforementioned patent application, the compressible body or outer layer disposed about a torso simulant must be directly cast onto rigid plates and vascular elements in order to properly simulate the appearance of the torso simulant, to properly simulate the functionality of the torso simulant, and to properly conceal vascular elements and pressure responsive areas along the torso simulant. The direct cast methodology is problematic because the liquid resin forming the compressible outer layer flows into the space between the rigid plates. After the resin cures, the solid, yet compressible resin resists closure between the plates and prevents proper compression and collapse of the vascular elements there between.
Accordingly, what is required is a torso simulant with blast and/or penetration injuries suitable for use as a training device for stemming blood loss that simulates the appearance, compressive properties, blood flow paths, and pressure responsive areas of a human torso.
Accordingly, what is required is a fabrication method for a torso simulant with blast and/or penetration injuries suitable for use as a training device for stemming blood loss whereby a resin is directly cast onto rigid elements disposed about a vascular simulant without impairing the mechanically-inducible compression of the vascular simulant by the rigid elements.